Congrats on your score, I've had my TA-15 for over a year now and it's been my main gigging amp since I've had it: my preferences when using the TA-15 have settled on using Channel 1 AC-jangly-clean (Normal mode, no master volume) and Channel 2 on Plexi-crunch-territory. The mid-sized venue we played last night warranted the amp being cranked to 25W and mic'd through two 1x12 Lonestar C90 loaded cabs, mini-stack configuration, like this (unfortunately the knobs settings in the pic aren't set to how I use it):
I love absolutely everything about this amp, not least its portability, but the tones available from this neat little rig never cease to amaze me! I'll get to a gig, setup, nice and easy, plug the pedal board in, power the rig up, and the first chord/note/whatever almost invariably brings a warm rush of pleasure and a delighted smile to my face: so easy, to carry, to setup, to dial in a great sound... the rare times that it doesn't bring me instant gratification is when I haven't checked before firing it up and a treble/bass knob, or maybe two, have been accidentally adjusted in transit or when taking it out of the padded bag.
How Mesa have got such great tones into such a small form factor amp is nothing less than astonishing: when faced with the choice of gigging with the TA-15 or my Lonestar Special 2x12 Combo, two rather similar sounding and similarly rated output amps, I'm reaching for the TA-15 9 times out of 10. The TransAtlantic range is, to me, so impressive I'm even considering trading the Lonestar in, an amp that I still absolutely love, for a TA-30 head and a nice TransAtlantic/Lonestar 2x12 or 4x10 cab.